package com.yc.spring_boot_04.component;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 登陆检测,不可以不登陆直接跳转到其他页面
 */
public class LoginHandlerInterceptor implements HandlerInterceptor {
    // 目标方法执行之前
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Object user = request.getSession().getAttribute("loginUser");
        if (user == null) {
            // 未登录,返回登陆界面
            request.setAttribute("msg", "没有权限.请先登录");
            request.getRequestDispatcher("/index.html").forward(request, response);
            return false;
        } else {
            // 已登陆.放行请求
            return true;
        }
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}
